Neurotropin® relieves oxaliplatin-induced neuropathy via Gi protein-coupled receptors in the monoaminergic descending pain inhibitory system

Repurposing of the analgesic Neurotropin for MASLD/MASH treatment

BACKGROUND

The prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) has increased in recent decades. Approximately 25% of patients with MASLD progress to metabolic dysfunction-associated steatohepatitis, which is characterized by hepatic steatosis plus hepatocyte damage, inflammation, and fibrosis. We previously reported that Neurotropin (NTP), a drug used for relieving pain in Japan and China, inhibits lipid accumulation in hepatocytes by preventing mitochondrial dysfunction. We hypothesized that inhibiting hepatic steatosis and inflammation by NTP can be an effective strategy for treating MASLD and tested this hypothesis in a MASLD mouse model.

METHODS

Six-week-old C57BL/6NJ male mice were fed a normal diet and normal drinking water or a high-fat diet with high fructose/glucose water for 12 weeks. During the last 6 weeks, the mice were also given high-dose NTP, low-dose NTP, or control treatment. Histologic, biochemical, and functional tests were conducted. MitoPlex, a new proteomic platform, was used to measure mitochondrial proteins, as mitochondrial dysfunction was previously reported to be associated with MASLD progression.

RESULTS

NTP inhibited the development of hepatic steatosis, injury, inflammation, and fibrosis induced by feeding a high-fat diet plus high fructose/glucose in drinking water. NTP also inhibited HSC activation. MitoPlex analysis revealed that NTP upregulated the expression of mitochondrial proteins related to oxidative phosphorylation, the tricarboxylic acid cycle, mitochondrial dynamics, and fatty acid transport.

CONCLUSIONS

Our results indicate that NTP prevents the development of hepatic steatosis, injury, and inflammation by preserving mitochondrial function in the liver and inhibits liver fibrosis by suppressing HSC activation. Thus, repurposing NTP may be a beneficial option for treating MASLD/metabolic dysfunction-associated steatohepatitis.

Centralizing the Knowledge and Interpretation of Pain in Chemotherapy-Induced Peripheral Neuropathy: A Paradigm Shift towards Brain-Centric Approaches

Chemotherapy-induced peripheral neuropathy (CIPN) is a side effect of cancer treatment, often linked with pain complaints. Patients report mechanical and thermal hypersensitivity that may emerge during chemotherapy treatment and may persist after cancer remission. Whereas the latter situation disturbs the quality of life, life itself may be endangered by the appearance of CIPN during cancer treatment. The causes of CIPN have almost entirely been ascribed to the neurotoxicity of chemotherapeutic drugs in the peripheral nervous system. However, the central consequences of peripheral neuropathy are starting to be unraveled, namely in the supraspinal pain modulatory system. Based on our interests and experience in the field, we undertook a review of the brain-centered alterations that may underpin pain in CIPN. The changes in the descending pain modulation in CIPN models along with the functional and connectivity abnormalities in the brain of CIPN patients are analyzed. A translational analysis of preclinical findings about descending pain regulation during CIPN is reviewed considering the main neurochemical systems (serotoninergic and noradrenergic) targeted in CIPN management in patients, namely by antidepressants. In conclusion, this review highlights the importance of studying supraspinal areas involved in descending pain modulation to understand the pathophysiology of CIPN, which will probably allow a more personalized and effective CIPN treatment in the future.

Animal models of chemotherapy-induced peripheral neuropathy for hematological malignancies: A review

Chemotherapy is one of the main treatments for hematologic malignancies. However, chemotherapy-induced peripheral neuropathy (CIPN) is one of the most common long-term toxic reactions in chemotherapy, and the occurrence of CIPN affects patients' quality of life and can cause interruption of chemotherapy in severe cases, thus reducing the efficacy of chemotherapy. We currently summarize the existing CIPN animal models, including the characteristics of several common animal models such as bortezomib-induced peripheral neuropathy, vincristine-induced peripheral neuropathy, and oxaliplatin-induced peripheral neuropathy. It was found that CIPN may lead to behavioral, histopathological, and neurophysiological changes inducing peripheral neuropathy. However, the mechanism of CIPN has not been fully elucidated, especially the prevention and treatment protocols need to be improved. Therefore, this review article summarizes the progress of research on CIPN animal models and the possible mechanisms and treatment of CIPN.

Involvement of Serotonergic System in Oxaliplatin-Induced Neuropathic Pain

Oxaliplatin is a chemotherapeutic agent widely used against colorectal and breast cancers; however, it can also induce peripheral neuropathy that can rapidly occur even after a single infusion in up to 80-90% of treated patients. Numerous efforts have been made to understand the underlying mechanism and find an effective therapeutic agent that could diminish pain without damaging its anti-tumor effect. However, its mechanism is not yet clearly understood. The serotonergic system, as part of the descending pain inhibitory system, has been reported to be involved in different types of pain. The malfunction of serotonin (5-hydroxytryptamine; 5-HT) or its receptors has been associated with the development and maintenance of pain. However, its role in oxaliplatin-induced neuropathy has not been clearly elucidated. In this review, 16 in vivo studies focused on the role of the serotonergic system in oxaliplatin-induced neuropathic pain were analyzed. Five studies analyzed the involvement of 5-HT, while fourteen studies observed the role of its receptors in oxaliplatin-induced allodynia. The results show that 5-HT is not involved in the development of oxaliplatin-induced allodynia, but increasing the activity of the 5-HT1A, 5-HT2A, and 5-HT3 receptors and decreasing the action of 5-HT2C and 5-HT6 receptors may help inhibit pain.

Therapeutic Agents for Oxaliplatin-Induced Peripheral Neuropathy; Experimental and Clinical Evidence

Oxaliplatin is an essential drug in the chemotherapy of colorectal, gastric, and pancreatic cancers, but it frequently causes peripheral neuropathy as a dose-limiting factor. So far, animal models of oxaliplatin-induced peripheral neuropathy have been established. The mechanisms of development of neuropathy induced by oxaliplatin have been elucidated, and many drugs and agents have been proven to have neuroprotective effects in basic studies. In addition, some of these drugs have been validated in clinical studies for their inhibitory effects on neuropathy. In this review, we summarize the basic and clinical evidence for the therapeutic effects of oxaliplatin. In basic research, there are many reports of neuropathy inhibitors that target oxidative stress, inflammatory response, sodium channel, transient receptor potential (TRP) channel, glutamate nervous system, and monoamine nervous system. Alternatively, very few drugs have clearly demonstrated the efficacy for oxaliplatin-induced peripheral neuropathy in clinical trials. It is important to activate translational research in order to translate basic research into clinical research.

Therapeutic Agents for Oxaliplatin-Induced Peripheral Neuropathy; Experimental and Clinical Evidence

Oxaliplatin is an essential drug in the chemotherapy of colorectal, gastric, and pancreatic cancers, but it frequently causes peripheral neuropathy as a dose-limiting factor. So far, animal models of oxaliplatin-induced peripheral neuropathy have been established. The mechanisms of development of neuropathy induced by oxaliplatin have been elucidated, and many drugs and agents have been proven to have neuroprotective effects in basic studies. In addition, some of these drugs have been validated in clinical studies for their inhibitory effects on neuropathy. In this review, we summarize the basic and clinical evidence for the therapeutic effects of oxaliplatin. In basic research, there are many reports of neuropathy inhibitors that target oxidative stress, inflammatory response, sodium channel, transient receptor potential (TRP) channel, glutamate nervous system, and monoamine nervous system. Alternatively, very few drugs have clearly demonstrated the efficacy for oxaliplatin-induced peripheral neuropathy in clinical trials. It is important to activate translational research in order to translate basic research into clinical research.

Therapeutic Agents for Oxaliplatin-Induced Peripheral Neuropathy; Experimental and Clinical Evidence

Oxaliplatin is an essential drug in the chemotherapy of colorectal, gastric, and pancreatic cancers, but it frequently causes peripheral neuropathy as a dose-limiting factor. So far, animal models of oxaliplatin-induced peripheral neuropathy have been established. The mechanisms of development of neuropathy induced by oxaliplatin have been elucidated, and many drugs and agents have been proven to have neuroprotective effects in basic studies. In addition, some of these drugs have been validated in clinical studies for their inhibitory effects on neuropathy. In this review, we summarize the basic and clinical evidence for the therapeutic effects of oxaliplatin. In basic research, there are many reports of neuropathy inhibitors that target oxidative stress, inflammatory response, sodium channel, transient receptor potential (TRP) channel, glutamate nervous system, and monoamine nervous system. Alternatively, very few drugs have clearly demonstrated the efficacy for oxaliplatin-induced peripheral neuropathy in clinical trials. It is important to activate translational research in order to translate basic research into clinical research.

Vortioxetine reduces pain hypersensitivity and associated depression-like behavior in mice with oxaliplatin-induced neuropathy

Chronic pain and depression commonly occur together so dual-acting agents might be particularly useful. The population of patients with chemotherapy-induced neuropathy is increasing in parallel with the increase of population of cancer survivors and there is a compelling need for satisfactory treatment of symptoms of neuropathy and concomitant depression. We examined the effects of vortioxetine, a novel antidepressant with unique mechanism of action, on pain hypersensitivity and depression-like behavior in oxaliplatin-induced neuropathy model in mice (OIPN). Vortioxetine (1-10 mg/kg, p.o.) significantly and dose-dependently reduced mechanical allodynia in von Frey test and cold allodynia in acetone test in OIPN mice, in both repeated prophylactic and acute therapeutic treatment regimens. It also reduced depression-like behavior in the forced swimming test in OIPN mice, in both treatment paradigms. Its antiallodynic and antidepressive-like effects were comparable to those exerted by duloxetine (1-15 mg/kg, p.o.). The antiallodynic and antidepressive-like effects of repeatedly administered vortioxetine might be related to the increased content of 5-hydroxytryptamine (5-HT) and noradrenaline (NA), detected in the brainstem of treated OIPN mice. These results indicate that vortioxetine could be potentially useful in prevention and treatment of chemotherapy-induced neuropathy, for the relief of pain and concomitant depressive symptoms. It should be further tested to this regard in clinical settings.

Neurotoxicity of antineoplastic drugs: Mechanisms, susceptibility, and neuroprotective strategies

This review summarizes the adverse effects on the central and/or peripheral nervous systems that may occur in response to antineoplastic drugs. In particular, we describe the neurotoxic side effects of the most commonly used drugs, such as platinum compounds, doxorubicin, ifosfamide, 5-fluorouracil, vinca alkaloids, taxanes, methotrexate, bortezomib and thalidomide. Neurotoxicity may result from direct action of compounds on the nervous system or from metabolic alterations produced indirectly by these drugs, and either the central nervous system or the peripheral nervous system, or both, may be affected. The incidence and severity of neurotoxicity are principally related to the dose, to the duration of treatment, and to the dose intensity, though other factors, such as age, concurrent pathologies, and genetic predisposition may enhance the occurrence of side effects. To avoid or reduce the onset and severity of these neurotoxic effects, the use of neuroprotective compounds and/or strategies may be helpful, thereby enhancing the therapeutic effectiveness of antineoplastic drug.

Neurotropin Inhibits Lipid Accumulation by Maintaining Mitochondrial Function in Hepatocytes via AMPK Activation

The accumulation of lipid droplets in the cytoplasm of hepatocytes, known as hepatic steatosis, is a hallmark of non-alcoholic fatty liver disease (NAFLD). Inhibiting hepatic steatosis is suggested to be a therapeutic strategy for NAFLD. The present study investigated the actions of Neurotropin (NTP), a drug used for chronic pain in Japan and China, on lipid accumulation in hepatocytes as a possible treatment for NAFLD. NTP inhibited lipid accumulation induced by palmitate and linoleate, the two major hepatotoxic free fatty acids found in NAFLD livers. An RNA sequencing analysis revealed that NTP altered the expression of mitochondrial genes. NTP ameliorated palmitate-and linoleate-induced mitochondrial dysfunction by reversing mitochondrial membrane potential, respiration, and β-oxidation, suppressing mitochondrial oxidative stress, and enhancing mitochondrial turnover. Moreover, NTP increased the phosphorylation of AMPK, a critical factor in the regulation of mitochondrial function, and induced PGC-1β expression. Inhibition of AMPK activity and PGC-1β expression diminished the anti-steatotic effect of NTP in hepatocytes. JNK inhibition could also be associated with NTP-mediated inhibition of lipid accumulation, but we did not find the association between AMPK and JNK. These results suggest that NTP inhibits lipid accumulation by maintaining mitochondrial function in hepatocytes via AMPK activation, or by inhibiting JNK.

Effect of the combination of high-frequency repetitive magnetic stimulation and neurotropin on injured sciatic nerve regeneration in rats

Repetitive magnetic stimulation is effective for treating posttraumatic neuropathies following spinal or axonal injury. Neurotropin is a potential treatment for nerve injuries like demyelinating diseases. This study sought to observe the effects of high-frequency repetitive magnetic stimulation, neurotropin and their combined use in the treatment of peripheral nerve injury in 32 adult male Sprague-Dawley rats. To create a sciatic nerve injury model, a 10 mm-nerve segment of the left sciatic nerve was cut and rotated through 180° and each end restored continuously with interrupted sutures. The rats were randomly divided into four groups. The control group received only a reversed autograft in the left sciatic nerve with no treatment. In the high-frequency repetitive magnetic stimulation group, peripheral high-frequency repetitive magnetic stimulation treatment (20 Hz, 20 min/d) was delivered for 10 consecutive days after auto-grafting. In the neurotropin group, neurotropin therapy (0.96 NU/kg per day) was administrated for 10 consecutive days after surgery. In the combined group, the combination of peripheral high-frequency repetitive magnetic stimulation (20 Hz, 20 min/d) and neurotropin (0.96 NU/kg per day) was given for 10 consecutive days after the operation. The Basso-Beattie-Bresnahan locomotor rating scale was used to assess the behavioral recovery of the injured nerve. The sciatic functional index was used to evaluate the recovery of motor functions. Toluidine blue staining was performed to determine the number of myelinated fibers in the distal and proximal grafts. Immunohistochemistry staining was used to detect the length of axons marked by neurofilament 200. Our results reveal that the Basso-Beattie-Bresnahan locomotor rating scale scores, sciatic functional index, the number of myelinated fibers in distal and proximal grafts were higher and axon lengths were longer in the high-frequency repetitive magnetic stimulation, neurotropin and combined groups compared with the control group. These measures were not significantly different among the high-frequency repetitive magnetic stimulation, neurotropin and combined groups. Therefore, our results suggest that peripheral high-frequency repetitive magnetic stimulation or neurotropin can promote the repair of injured sciatic nerves, but their combined use seems to offer no significant advantage. This study was approved by the Animal Ethics Committee of the Affiliated Changzhou No. 2 People’s Hospital of Nanjing Medical University, China on December 23, 2014 (approval No. 2014keyan002-01).

Identification of drug transporters contributing to oxaliplatin-induced peripheral neuropathy

Oxaliplatin is widely used as a key drug in the treatment of colorectal cancer. However, its administration is associated with the dose-limiting adverse effect, peripheral neuropathy. Platinum accumulation in the dorsal root ganglion (DRG) is the major mechanism responsible for oxaliplatin-induced neuropathy. Some drug transporters have been identified as platinum complex transporters in kidney or tumor cells, but not yet in DRG. In the present study, we investigated oxaliplatin transporters and their contribution to peripheral neuropathy. We identified 12 platinum transporters expressed in DRG with real-time PCR, and their transiently overexpressing cells were established. After exposure to oxaliplatin, the accumulation of platinum in these overexpressing cells was evaluated using a coupled plasma mass spectrometer. Octn1/2- and Mate1-expressing cells showed the intracellular accumulation of oxaliplatin. In an animal study, peripheral neuropathy developed after the administration of oxaliplatin (4 mg/kg, intravenously, twice a week) to siRNA-injected rats (0.5 nmol, intrathecally, once a week) was demonstrated with the von Frey test. The knockdown of Octn1 in DRG ameliorated peripheral neuropathy, and decreased platinum accumulation in DRG, whereas the knockdown of Octn2 did not. Mate1 siRNA-injected rats developed more severe neuropathy than control rats. These results indicate that Octn1 and Mate1 are involved in platinum accumulation at DRG and oxaliplatin-induced peripheral neuropathy.

Upregulation of glycosaminoglycan synthesis by Neurotropin in nucleus pulposus cells via stimulation of chondroitin sulfate N-acetylgalactosaminyltransferase 1: A new approach to attenuation of intervertebral disc degeneration

It is suggested that most cases of low back pain are related to degeneration of intervertebral discs. Disc degeneration is a chronic and progressive disease and the search for effective medical treatments continues. Neurotropin is widely used in Japan and China to treat low back pain and neck–shoulder–arm syndrome. The present study aimed to investigate the effect of Neurotropin on glycosaminoglycan synthesis in nucleus pulposus cells. Cultured human nucleus pulposus cells were treated with Neurotropin every second day for two weeks. Production of glycosaminoglycan was assessed using a dimethyl-methylene blue assay and PicoGreen was used to measure DNA content. Microarray analysis, real-time PCR, and western blotting were performed to assess the biological processes related to Neurotropin-stimulated glycosaminoglycan synthesis. The results showed that the level of glycosaminoglycan normalized to DNA content was significantly upregulated by the addition of Neurotropin. Gene expression profiling showed over two-fold upregulation of 697 genes in response to Neurotropin treatment. Among these genes, ontological analysis suggested significant implication of phosphatidylinositol 3-kinase signaling, and analysis focused on this pathway demonstrated marked upregulation of angiopoietin 1 and insulin-like growth factor 1. Activation of phosphorylation of the signal transducer protein AKT was detected by western blotting. Of the genes related to sulfated glycosaminoglycan synthesis, the greatest increase in mRNA levels was observed for chondroitin sulfate N-acetylgalactosaminyltransferase 1, an enzyme initiating synthesis of chondroitin sulfate side chains attached to a core protein of aggrecan, which is a predominant disc matrix component. These findings suggest that Neurotropin may activate the phosphatidylinositol 3-kinase–AKT pathway and stimulate glycosaminoglycan synthesis through upregulation of expression of mRNA for chondroitin sulfate N-acetylgalactosaminyltransferase 1. Because there was no cytotoxic cellular growth inhibition, Neurotropin treatment might offer an accessible therapeutic strategy for intervertebral disc degeneration.

Neurotropin inhibits neuroinflammation via suppressing NF-κB and MAPKs signaling pathways in lipopolysaccharide-stimulated BV2 cells

Neurotropin (NTP) is a widely used drug in China and Japan mainly for the treatment of chronic pain and peripheral inflammation. Nevertheless, the effects of NTP on neuroinflammation have not been explored. In this study, we investigated the anti-inflammatory effects of NTP in lipopolysaccharide (LPS)-stimulated BV-2 microglial cells and its underlying mechanisms. BV-2 cells were pretreated with NTP for 12 h before exposure to LPS. The expression of pro-inflammatory cytokines (TNF-α and IL-6) were detected by RT-PCR and EILSA at mRNA and protein levels, respectively. Western blotting was conducted to measure the protein levels of major genes in MAPKs and NF-κB signaling pathways. Results demonstrated that NTP could attenuate the production of pro-inflammatory cytokines. Furthermore, NTP inhibited the activation of NF-κB signaling by decreasing the translocation of NF-κB p65 to the nucleus and suppressed the MAPKs signaling pathway via inhibition of the phosphorylation of p38, ERK and JNK. Taken together, these findings suggest that neurotropin exerts anti-inflammatory effects by suppressing the production of pro-inflammatory mediators via inhibition of NF-κB and MAPKs signaling pathways in LPS-stimulated BV-2 cells.

Neurotropin® Accelerates the Differentiation of Schwann Cells and Remyelination in a Rat Lysophosphatidylcholine-Induced Demyelination Model

Neurotropin^® (NTP), a non-protein extract of inflamed rabbit skin inoculated with vaccinia virus, is clinically used for the treatment of neuropathic pain in Japan and China, although its effect on peripheral nerve regeneration remains to be elucidated. The purpose of this study was to investigate the effects of NTP on Schwann cells (SCs) in vitro and in vivo, which play an important role in peripheral nerve regeneration. In SCs, NTP upregulated protein kinase B (AKT) activity and Krox20 and downregulated extracellular signal-regulated kinase1/2 activity under both growth and differentiation conditions, enhanced the expression of myelin basic protein and protein zero under the differentiation condition. In a co-culture of dorsal root ganglion neurons and SCs, NTP accelerated myelination of SCs. To further investigate the influence of NTP on SCs in vivo, lysophosphatidylcholine was injected into the rat sciatic nerve, leading to the focal demyelination. After demyelination, NTP was administered systemically with an osmotic pump for one week. NTP improved the ratio of myelinated axons and motor, sensory, and electrophysiological function. These findings reveal novel effects of NTP on SCs differentiation in vitro and in vivo, and indicate NTP as a promising treatment option for peripheral nerve injuries and demyelinating diseases.

Neurotropin® alleviates hippocampal neuron damage through a HIF-1α/MAPK pathway

AIMS

The main purpose was to verify the potent capacity of Neurotropin® against neuronal damage in hippocampus and to explore its underlying mechanisms.

METHODS

HT22 cells were treated with 40 μmol/L Aβ_25-35 in the presence of various concentrations of Neurotropin® or in its absence. The cell viability was assessed with a CCK-8 assay, and flow cytometry was used to measure cell apoptosis, intracellular ROS levels, and mitochondrial membrane potential. Aβ plaques were examined by Bielschowsky silver staining, and the activities of antioxidants were detected in hippocampus of APP/PS1 mice after Neurotropin® treatment. The expression of proteins, including HIF-1α, Bcl-2, Bax, and MAPKs signaling molecules was evaluated by Western blot.

RESULTS

Neurotropin® significantly reversed the cell injury induced by Aβ_25-35 through increasing cell viability and mitochondrial membrane potential, decreasing intracellular ROS and cell apoptosis of HT22 cells (P<.05). Furthermore, Neurotropin® markedly reduced the formation of Aβ plaques and upregulated the activities of antioxidants (P<.05). Additionally, the protein expression of HIF-1α, p-ERK1/2, p-JNK, and p-P38 was significantly inhibited in hippocampus of APP/PS1 mice.

CONCLUSIONS

Neurotropin® exhibited a potent neuroprotective effect on inhibiting Aβ-induced oxidative damage and alleviating Aβ deposition in hippocampus via modulation of HIF-1α/MAPK signaling pathway.

Neurotropin attenuates local inflammatory response and inhibits demyelination induced by chronic constriction injury of the mouse sciatic nerve

Neuropathic pain caused by nerve damage in the central and/or peripheral nervous systems is a refractory disorder and the management of such chronic pain has become a major issue. Neurotropin is a drug widely used in Japan and China to treat chronic pain. Although Neurotropin has been demonstrated to suppress chronic pain through the descending pain inhibitory system, the mechanism of analgesic action in the peripheral nervous system remains to be elucidated. In this study, we investigated the local effects of Neurotropin on peripheral nerve damage in a chronic constriction injury (CCI) model. Neurotropin reduced mRNA expressions of IL-1β, IL-6, and TNF-α in the sciatic nerve 1 day after the injury. Activation of Erk was also inhibited locally in the Neurotropin treatment group. Since Erk activation results in demyelination along with dedifferentiation of Schwann cells, we investigated the expression level of myelin basic protein. Five days after the injury, Neurotropin attenuated the downregulation of myelin basic protein in the sciatic nerve in the CCI model. Local effects of Neurotropin around the injury site may result in discovery of new treatments for not only neuropathic pain but also demyelinating diseases and peripheral nervous system injury.

Neurotropin suppresses inflammatory cytokine expression and cell death through suppression of NF-κB and JNK in hepatocytes

Inflammatory response and cell death in hepatocytes are hallmarks of chronic liver disease, and, therefore, can be effective therapeutic targets. Neurotropin® (NTP) is a drug widely used in Japan and China to treat chronic pain. Although NTP has been demonstrated to suppress chronic pain through the descending pain inhibitory system, the action mechanism of NTP remains elusive. We hypothesize that NTP functions to suppress inflammatory pathways, thereby attenuating disease progression. In the present study, we investigated whether NTP suppresses inflammatory signaling and cell death pathways induced by interleukin-1β (IL-1β) and tumor necrosis factor-α (TNFα) in hepatocytes. NTP suppressed nuclear factor-κB (NF-κB) activation induced by IL-1β and TNFα assessed by using hepatocytes isolated from NF-κB-green fluorescent protein (GFP) reporter mice and an NF-κB-luciferase reporter system. The expression of NF-κB target genes, Il6, Nos2, Cxcl1, ccl5 and Cxcl2 induced by IL-1β and TNFα was suppressed after NTP treatment. We also found that NTP suppressed the JNK phosphorylation induced by IL-1β and TNFα. Because JNK activation contributes to hepatocyte death, we determined that NTP treatment suppressed hepatocyte death induced by IL-1β and TNFα in combination with actinomycin D. Taken together, our data demonstrate that NTP attenuates IL-1β and TNFα-mediated inflammatory cytokine expression and cell death in hepatocytes through the suppression of NF-κB and JNK. The results from the present study suggest that NTP may become a preventive or therapeutic strategy for alcoholic and non-alcoholic fatty liver disease in which NF-κB and JNK are thought to take part.